Assistant professor, Stanford University, Stanford, CA
An investigation was performed to study the load-carrying capability of fiber-reinforced composite shells subjected to quasi-static transverse crushing loads. Both experimental and analytical work have been performed. Experiments on T300/934 and T300/976 graphite/epoxy materials were first conducted on composite cylinders subjected to crushing loads. An analytical model was also developed which was based on a progressive damage analysis. The model consists of a stress analysis and a failure analysis. Deformations, stresses, and strains in the composite cylinders were analyzed based on the large deformation theory. Damage accumulation and the residual stiffness and strength of the tubes were evaluated by a combination of appropriate failure criteria with property degradation models. Based on the model, a nonlinear finite element program, designated as “PDTUBE,” was developed. The code is capable of assessing damage in the laminates and predicting residual stiffness and strength of composite cylinders subjected to transverse crushing loads. An excellent agreement was found between the computer simulations and the test results. A parametric study was also conducted to determine the effects of material properties, ply orientation, and geometries on the response of cylindrical composite shells.
Paper ID: CTR10206J